1 // SPDX-License-Identifier: GPL-2.0 1
2 /* Copyright (C) 2019 Hangzhou C-SKY Microsyst
3
4 #include <linux/perf_event.h>
5 #include <linux/uaccess.h>
6
7 #include <asm/stacktrace.h>
8
9 static bool fill_callchain(void *entry, unsign
10 {
11 return perf_callchain_store(entry, pc)
12 }
13
14 /*
15 * This will be called when the target is in u
16 * This function will only be called when we u
17 * "PERF_SAMPLE_CALLCHAIN" in
18 * kernel/events/core.c:perf_prepare_sample()
19 *
20 * How to trigger perf_callchain_[user/kernel]
21 * $ perf record -e cpu-clock --call-graph fp
22 * $ perf report --call-graph
23 *
24 * On RISC-V platform, the program being sampl
25 * need to be compiled with -fno-omit-frame-po
26 * the user stack will not contain function fr
27 */
28 void perf_callchain_user(struct perf_callchain
29 struct pt_regs *regs)
30 {
31 arch_stack_walk_user(fill_callchain, e
32 }
33
34 void perf_callchain_kernel(struct perf_callcha
35 struct pt_regs *reg
36 {
37 walk_stackframe(NULL, regs, fill_callc
38 }
39
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.